Face ID stopped working

If you're sure that nothing (cover, screen protector, dirt) interferes with your front camera (remove any obstacles, if present), see this support article:--> If Face ID isn't working on your iPhone or iPad Pro and/or this one:--> If an alert says Face ID has been disabled on your iPhone or iPad Pro

If the issue persists, after performing all the steps provided in the above support articles, contact Apple Support directly, using this specific link:--> Apple Support , or make an appointment and have your device inspected at an Apple Store or AASP (Apple Authorized Service Provider) among this list:--> Apple - Find Locations - Location Selector. After checking it out, they'll give you all the available options.

Regards

Giulio

If your iPhone is an iPhone X or newer, and not an iPhone 6, you will have to contact the official Apple Support, to get Face ID repaired.

You can use this link as a start:

Get iPhone Support Apple

If this is an iPhone 6 and the Touch ID button does not recognise your fingerprint anymore, only the official Apple Support can fix this.

Give them a call by selecting the phone number for your region from this Apple page:

Contact Apple for support and service - Apple Support

Or check your service options on this Apple page:

iPhone Repair & Service - Apple Support